Bernard moebius



(No Mode1.\

B. MOEBIUS.

PROCESS 0F TREATING BASE BULLION AMALGAM.

Patented Aug. 16, 1892.

INVENTR' mu Ev.

run Noms Penas co.. wmuwo UNITED STATES PATENT OFFICE.

BERNARD MOEBIUS, OF NEW YORK, N. Y.

PROCESS OF TREATING BAASEBULLIONAMALGAM.

SPECIFICATION forming part of Letters Patent No. 480,956, dated August 16, 1892. Application letl December 31, 1891. Serial No, 416,663. (No specimens.)

T all whom t may concern:

Be it known that I, BERNAEDhMoEBIUs, a citizen of the German Empire, having declared my intention to become a citizen of the United States, and a resident of New York, in the county and State of New York, have invented a new and useful Improvement in the Process of Treating Base-Bullion Amalgam, of which the following is a specication.

Heretofore the bullion resulting from retorting (distilling off the mercury) of the amalgam containing, besides silver and gold, a large percentage of copper and variable quantities of lead, antimony, tbc., has been refined by different more or less tedious and expensive methods, subject to great loss of silver ,by volatilization. The method most generally used consists in cupelling the bullion with lead, whereby the impurities-such as copper, &c.-go into the litharge, but with them also considerable silver. As the byproducts have to be worked over again, this method can only be employed at smelting and refining Works. Another method frequently used consists in melting and granulating the retorted bullion and heating the same in a reverberatory or roasting furnace, so as to oxidize the copper. The oxidation, however, does not penetrate deep into the granules, but only affects the surface. The roasted material is treated with sulphuric acid, which dissolves the scale of oxide of copper, and the remaining part goes to the roasting-furnace again, and so on, until all of the copper is oxidized and dissolved. This method involves a great loss of time, labor, and fuel.

The object of my invention is to have the base-bullion resulting from retorting in such a condition that the greater part of the copper is already oxidized, and therefore readily dissolved by acids without requiring any further roasting, and for this purpose, during and after retorting, I subject the heated mass to a comminuting action, While at the same time exposing it to the oxidizing action of a current of air, so as to obtain a nely-divided residue containing oxidized base metals, together with the precious metals, and which residue after leaching leaves a bullion sufficiently rich to be parted by any partingprocess.

In the annexed drawings I have shown an example of an apparatus for carrying out my process.

In the drawings, Figure 1 is a front View of the apparatus, and Fig. 2 a longitudinal section of the same in the plane at, Fig. l.

Similar letters refer to corresponding parts.

A is a cast-iron cylinder or retort with a flanged neck a. The front end of the retort is closed by a door Gr, having a hole ZJ in the center, which is closed by a screw-cap c. The door Gis bolted to a flange g of the retort and forms a stopper, having an extension d d e e, the cylindrical part CZ d of which is surrounded by asbestus rope or other suitable packing material. The air-spacefbetween the cover and its extension keeps the heat from the front part and also prevents the accumulation in front of the material to be treated.

^ The retort A is mounted in a suitable furnace, so as to be free to rotate. K is the lireplace, L the ash-pit, and M the chimney, of the furnace. The flange gis supported upon rollers 7L h, mounted in brackets secured to the furnace-plates. To the neck a of the retort is bolted an extension B, the flange c'of which is supported upon rollers j.

Slow rotary motion is imparted to the retort A by suitable means, such as the chain 7o, passing over a sprocket-flange Zon the retort and over a sprocket-Wheel 'm on driving-shaft n. Iron or stone balls H or other suitable bodies serve to comminute the material within the rotating retort.

By means of a stuffing-box O the extension B of the neck ct is connected with a U shaped condenser-pipe D, the upper end of which is connected with the chimney by a pipe E. Draft through the retort may be increased when desired, by well-known means. The two vertical branches of the pipeD are cooled by water in vessels F F', the water entering near the bottom and leaving near the top. The lowest part of the condenser-pipe is provided with a small discharge-pipe L, formingatrap, so that the condensed mercury can run into a tank J, but preventing air passing into the condenser.

My invention is not restricted to the use of the apparatus shown and described, since a great variety of apparatus may be designed for accomplishing the same result.

IOO

In carrying out my process I remove the door Gr and charge the retort with the amalgam in small lum-ps, togetherwith a number of balls H, and then replace the door G with the cap c screwed on, whereupon the cylinder is set in rotation and a good heat given. When distillation is fairly under way, I- remove the cap c, so as to allow atmospheric air to be drawn through the retort for the purpose of oxidizing the base metals. The mercury is condensed in the pipe D and flows through the pipe I into the tank J. This arrangement admits of the-close observationoi:`

the progress of distillation by the quantity of condensed mercury discharged through thepipe I. After distillation has ceased and a test sample of the retorted bullion showsthat the base metals are suiiiciently oxidized, yfiring is stopped, the door G removed,.andthe mass Withdrawn from the furnace.` thus obtained as a powder isi` leached inthe well-known manner with, diluted sulphumc acid which dissolves the oxideot copper as sulphate, which is used over again in the process of amalgamating. In remote locali-ties where sulphuric acid is expensive I use by preference sulphurous acid` for leaching. I` produce the sulphurous acid by burningfsulphur in the usual manner vand drawing the' products of combustion by a lead-lined steamjet apparatus (exhauster and compressorlintol the leachingtanks containing the retorted bullion-powderand water. In the presence of metallic oxides, air, and steam thesulplrutrL ous acid is rapidly converted into sulphuric acidi,whichlrapidly dissolves the oxide ot copper, while forming with the oXideof leady a, sulphate which remains undjssolved with thef precious metals, but goes intoA thefslag when the bullionis melted;

While by the ordinary retortingth'e resulting bullion is in lumps which are scarcelyoxii dized, by my processit is obtained as a powder because during the process the chargev is 'llhe bullion 1 dation, whereby the whole or the greater part of the base` metals is oxidized and prevented from agglomerating. Dierent means may be used for comminuting the mass in the distillin g apparatus, although a rotary retort and .balls are the simplest. For some material the rotation of the retort without balls willtsuiiiciently agitate the mass to prevent sticking together.

What I claim as my invention, and desire to secure by Letters Patent, is'- 1., The process of treating amalgam of the character specified, which consists in'charging the same into an apparatus for distilling o and collecting the mercury and subjecting lthe heated chargetoa comminuting action, Ywhile at the same time oxidizing the base metals by a. current of air.

2; Thev process ot" treating amalgamof` the :character specified, which consists in charging the same into an apparatus for distilling oit and collectingthe mercury, subjecting the 4at the same time oxidizing the base metals by a current of` air, and leaching the finely-divided residue, substantially as specified;

3. The process ot" treatingl amalgam of' the character specified, which consists inV charging the same intoan apparatus for distilling oft and collecting the mercury, subjectingthe at thesame time oxidizing the base metalsfby a current of air, and leaching the iinely-dividedresidue bysuilphuric acid; substantially as speciied.

In testimony that I claim the foregoingas my invention I' have signed my name, in pres- .encelof twowitnessesmhis 30th day of December, 1891. Y

BERNARD VMOEBIUS.

Witnesses:

A. FABER DU FAUR, J'osEBH ELIAS.

heated charge to a comminuting action, while heatedy chargeto a comminuting action, while subjected to a comminuting action and to oxi- 

